-käse durch isoelektrische Fokussierung in harnstoffhaltigen Polyacrylamidgelen (Откриване на краве мляко в овче и козе мляко и сирене чрез изоелектрическо фокусиране в полиакриламидни гелове, съдържащи уреа).
Krause I., Berner I, Klostermeyer H.: Sensitive detection of cow milk in ewe and goat milk and cheese by carrier ampholyte – and carrier ampholyte/immobilized pH gradient – isoelectric focusing of γ-caseins using plasmin as signal amplifier, v: Electrophoresis-Forum 89 (B. J. Radola, ur.), Bode-Verlag, München, 1989., str.